/01-auto-arena

name: 01-auto-arena
description: >
  Automatically evaluate and compare multiple AI models or agents without
  pre-existing test data. Generates test queries from a task description,
  collects responses from all target endpoints, auto-generates evaluation
  rubrics, runs pairwise comparisons via a judge model, and produces
  win-rate rankings with reports and charts. Supports checkpoint resume,
  incremental endpoint addition, and judge model hot-swap.
  Use when the user asks to compare, benchmark, or rank multiple models
  or agents on a custom task, or run an arena-style evaluation.

Auto Arena Skill

End-to-end automated model comparison using the OpenJudge `AutoArenaPipeline`:

1. **Generate queries** — LLM creates diverse test queries from task description 2. **Collect responses** — query all target endpoints concurrently 3. **Generate rubrics** — LLM produces evaluation criteria from task + sample queries 4. **Pairwise evaluation** — judge model compares every model pair (with position-bias swap) 5. **Analyze & rank** — compute win rates, win matrix, and rankings 6. **Report & charts** — Markdown report + win-rate bar chart + optional matrix heatmap

Prerequisites

# Install OpenJudge
pip install py-openjudge

# Extra dependency for auto_arena (chart generation)
pip install matplotlib

Gather from user before running

| Info | Required? | Notes | |------|-----------|-------| | Task description | Yes | What the models/agents should do (set in config YAML) | | Target endpoints | Yes | At least 2 OpenAI-compatible endpoints to compare | | Judge endpoint | Yes | Strong model for pairwise evaluation (e.g. `gpt-4`, `qwen-max`) | | API keys | Yes | Env vars: `OPENAI_API_KEY`, `DASHSCOPE_API_KEY`, etc. | | Number of queries | No | Default: `20` | | Seed queries | No | Example queries to guide generation style | | System prompts | No | Per-endpoint system prompts | | Output directory | No | Default: `./evaluation_results` | | Report language | No | `"zh"` (default) or `"en"` |

Quick start

CLI

# Run evaluation
python -m cookbooks.auto_arena --config config.yaml --save

# Use pre-generated queries
python -m cookbooks.auto_arena --config config.yaml \
  --queries_file queries.json --save

# Start fresh, ignore checkpoint
python -m cookbooks.auto_arena --config config.yaml --fresh --save

# Re-run only pairwise evaluation with new judge model
# (keeps queries, responses, and rubrics)
python -m cookbooks.auto_arena --config config.yaml --rerun-judge --save

Python API

import asyncio
from cookbooks.auto_arena.auto_arena_pipeline import AutoArenaPipeline

async def main():
    pipeline = AutoArenaPipeline.from_config("config.yaml")
    result = await pipeline.evaluate()

    print(f"Best model: {result.best_pipeline}")
    for rank, (model, win_rate) in enumerate(result.rankings, 1):
        print(f"{rank}. {model}: {win_rate:.1%}")

asyncio.run(main())

Minimal Python API (no config file)

import asyncio
from cookbooks.auto_arena.auto_arena_pipeline import AutoArenaPipeline
from cookbooks.auto_arena.schema import OpenAIEndpoint

async def main():
    pipeline = AutoArenaPipeline(
        task_description="Customer service chatbot for e-commerce",
        target_endpoints={
            "gpt4": OpenAIEndpoint(
                base_url="https://api.openai.com/v1",
                api_key="sk-...",
                model="gpt-4",
            ),
            "qwen": OpenAIEndpoint(
                base_url="https://dashscope.aliyuncs.com/compatible-mode/v1",
                api_key="sk-...",
                model="qwen-max",
            ),
        },
        judge_endpoint=OpenAIEndpoint(
            base_url="https://api.openai.com/v1",
            api_key="sk-...",
            model="gpt-4",
        ),
        num_queries=20,
    )
    result = await pipeline.evaluate()
    print(f"Best: {result.best_pipeline}")

asyncio.run(main())

CLI options

| Flag | Default | Description | |------|---------|-------------| | `--config` | — | Path to YAML configuration file (required) | | `--output_dir` | config value | Override output directory | | `--queries_file` | — | Path to pre-generated queries JSON (skip generation) | | `--save` | `False` | Save results to file | | `--fresh` | `False` | Start fresh, ignore checkpoint | | `--rerun-judge` | `False` | Re-run pairwise evaluation only (keep queries/responses/rubrics) |

Minimal config file

task:
  description: "Academic GPT assistant for research and writing tasks"

target_endpoints:
  model_v1:
    base_url: "https://api.openai.com/v1"
    api_key: "${OPENAI_API_KEY}"
    model: "gpt-4"
  model_v2:
    base_url: "https://api.openai.com/v1"
    api_key: "${OPENAI_API_KEY}"
    model: "gpt-3.5-turbo"

judge_endpoint:
  base_url: "https://api.openai.com/v1"
  api_key: "${OPENAI_API_KEY}"
  model: "gpt-4"

Full config reference

task

| Field | Required | Description | |-------|----------|-------------| | `description` | Yes | Clear description of the task models will be tested on | | `scenario` | No | Usage scenario for additional context |

target_endpoints.\<name\>

| Field | Default | Description | |-------|---------|-------------| | `base_url` | — | API base URL (required) | | `api_key` | — | API key, supports `${ENV_VAR}` (required) | | `model` | — | Model name (required) | | `system_prompt` | — | System prompt for this endpoint | | `extra_params` | — | Extra API params (e.g. `temperature`, `max_tokens`) |

judge_endpoint

Same fields as `target_endpoints.<name>`. Use a strong model (e.g. `gpt-4`, `qwen-max`) with low temperature (~0.1) for consistent judgments.

query_generation

| Field | Default | Description | |-------|---------|-------------| | `num_queries` | `20` | Total number of queries to generate | | `seed_queries` | — | Example queries to guide generation | | `categories` | — | Query categories with weights for stratified